Aqueous extraction of natural dyes from Petrocarpus santalinus tree wood and dyeing of the following natural fibres: banana fibre, screw fine fibre, pineapple fibre, sisal fibre, korai and palm leaf using various mordants to fix the colour in the fibre materials were performed. Salt, sodium bicarbonate, oxalic acid, tannic acid, ferrous ammonium sulphate, stannous chloride (tin metal powder), alum and tamarind (Tamarindus indica) were used as a mordant for the dying of the natural fibres. Petrocarpus santalinus dye was effectively dyed on natural fibres using different mordants, producing different colours like tomato, maroon, orange red, chocolate, brown, quarry red, black, brick red, tile red, terra colla, sunbaked clay, gray, brick red, victorian red, firebrick, brown, crimson and orange, using these mordants.